NAME: caldatm PURPOSE: Find year, month, day, hour, minute, second from Julian Date. CATEGORY: Astronomy CALLING SEQUENCE: caldatm, jd, y, m, d, hour, min, sec INPUTS: jd = Julian day number (like 2447000.5). in KEYWORD PARAMETERS: OUTPUTS: y = year (like 1987). out m = month number (like 7). out d = day of month (like 23). out hour = hour of day (like 12). out min = minute of day (like 0). out sec = second of day (liek 0.0). out COMMON BLOCKS: NOTES: This routine is based on the formulas given in "Astronomical Formulae for Calculators," 2nd. ed., by Jean Meeus on pages 23-29. This algorithm works for any date in either the Julian calendar (before 1582 October 4) or the Gregorian calendar except for negative Julian Day numbers. MODIFICATION HISTORY: M. Buie, 1991 Oct 10, Lowell Observatory DWL, August 6, 1993, Modifications to operate with vector input.